FR2609795A1 - OPTOELECTRONIC PACKET CONTROL METHOD ON ALL ITS FACES - Google Patents

Abstract

A) OPTO-ELECTRONIC PROCESS FOR CHECKING PACKAGES 2, ON ALL OF ITS FACES; B) METHOD CHARACTERIZED IN THAT IT CONSISTS OF BRINGING THE SUCCESSIVE PACKAGES 2 ALONG A FIRST CONVEYOR 13 IN CONTACT WITH A FIRST PART OF EACH PACKAGE, OF TRANSFERRING THE PACKAGES TO A SECOND CONVEYOR 14 IN CONTACT WITH A SECOND PART OF EACH PACKAGE, TO BE MADE BY OPTO-ELECTRONIC MEANS 27, 28 A FIRST SURFACE OF PART OF THE SURFACE OF PACKAGE 2 ON THE FIRST CONVEYOR 13, AND A SECOND SURVEY OF THE REMAINING PART OF PACKAGE 2 ON THE SECOND CONVEYOR 14, AND TO COMPARE THESE TWO SUCCESSIVE SURVEYS WITH REFERENCE IMAGES TO PRODUCE CONFORMITY SIGNALS COMMANDING A REJECTION DEVICE 38; C) THE INVENTION RELATES TO AN OPTO-ELECTRONIC PROCESS FOR CHECKING PACKAGES ON ALL ITS FACES.

Description

"Optoelectronic method of controlling packets on all sides"

  The invention relates to an optically

  electronic packet control.

  On packaging machines, it is well known to use optoelectronic devices generally constituted by television cameras, to control the surface finish of packages produced by the machine; this surface control is generally performed by passing the packets on a conveyor belt, between two or more television cameras generally offset relative to one another

to others.

  Since the packages are placed so that one of their faces is in contact with the conveyor belt, it is obvious that this face at least can not be controlled. Such a limitation can be problematic in cases where not only a surface inspection is required, but also a precise dimensional inspection of all the faces

of the package.

  The object of the invention is to create a method for controlling the surface characteristics of a package, which makes it possible to overcome the above disadvantages. For this purpose, the invention relates to an opto-electronic method of controlling packets, characterized in that it comprises the various steps of: successively bringing the packets along a first

  conveyor device defining a first override

  transport face arranged to come into contact with a first part of each package; successively transferring the packets onto a second conveyor device defining a second transport surface arranged to come into contact with a second part of each package;

  - perform, through optoelectronic means

  first section of the outer surface of each package as it passes along the first conveyor device, and a second reading of the remaining part of the outer surface of each package as it passes the along the second conveyor device; and compare the images obtained by these two operations of readings made

  by opto-electronic means, to the reference images

  to produce compliance signals

  for controlling a reject device.

  Further improvements according to the invention are characterized in that: the first and second readings are made by the optoelectronic television camera means designed to examine the packets from two different angles; the first and second readings are made by sending to a single television camera optoelectronic device a first image and a second image of each of the packets observed under the two different angles;

  - the two images are transmitted to opto-

  electronic single TV camera using

  at least one bundle of optical fibers.

  Two nonlimiting examples of embodiment of the invention will now be described in detail with reference to the accompanying drawings in which: FIG. 1 is a schematic perspective view and partly in the form of a block diagram of a first device; opto-electronic packet control system implementing the method according to the invention; and FIG. 2 is a diagrammatic perspective view, partly in the form of a block diagram, of a second optoelectronic device for controlling the

  packets implementing the method according to the invention.

  In FIG. 1, the reference numeral 1 denotes an optoelectronic control device intended to control the external finish, that is to say the correct production, of a number of packets 2 which are passed successively along a path

  given by a conveyor system 3.

  Each package 2 is essential

  in the form of a rectangular parallelepiped having two end faces 4 and 5, an upper face 6 and a lower face 7 parallel to each other, and two side faces 8 and 9 parallel to each other. other and perpendicular to all faces

4, 5, 6 and 7.

  The conveyor system 3 comprises an input conveyor 10 consisting of a belt 11 which is rolled around horizontal rollers 12 and coming into contact with the face or lower part 7 of the packets 2. The conveyor 10 is designed to support and bring the packets successively. 2 on a pair of conveyors 13 and 14 designed to support the packs 2 by suction means. The conveyor 13 comprises a belt 15 permeable to air and wound around vertical rollers 16 placed at the opposite ends of a suction chamber 17, this belt 15 being in contact with the side or side portion 8 of the packets 2. conveyor 14 comprises a belt 18 permeable to air and wound around vertical rollers 19 placed at the opposite ends of a suction chamber 20, this belt 18 being in contact with the face or part

lateral 9 packets 2.

  Finally, the conveyor system 3 comprises an output conveyor 21 aligned with the input conveyor 10 and comprising a belt 22 wound around horizontal rollers 23. The two conveyors 10 and 20 comprise upper guide walls 24 of the

packages 2.

  A portion of the exit end of the conveyor 10 comes below the conveyor 13. The conveyor part of the belt 15 forming part of this conveyor 13 replaces the missing end portion of one of the walls 24 placed at the end of the conveyor 13. above the conveyor 10. In the same way, the two conveyors 13 and 14 overlap partially over a length substantially equal to the length of a pack 2, this length being measured in the direction of travel indicated by the arrow 25. In particular, the conveying surfaces of the belts 15 and 18 are arranged so as to come partially opposite one another, and are

  separated by a distance substantially equal to the thickness

of a package 2.

  A portion of the inlet end of the conveyor 21 comes below an outlet portion of the conveyor 14. The conveyor portion of the belt 18 forming part of the conveyor 14, replaces the missing inlet portion of the conveyor belt. one of the walls 24 placed

above the conveyor 21.

  The opto-electronic device 1 comprises opto-electronic television camera means themselves constituted by a television camera 26 placed in the vicinity of the conveyor 13 and forming, by

  relative to the transport surface of the corresponding belt.

  15, an angle such that it can see, through optical means constituted by a lens 27, the three surfaces 5, 7 and 9 of a package 2 placed on the conveyor 13 in a first position given in the vicinity the end of the conveyor 14. As shown in Figure 1, the camera

  television 26 comprises a second device opto-

  electronic lens constituted by a lens 28 and connected to the television camera 26 via an optical fiber bundle 29. The lens 28 is placed in the vicinity of the conveyor 14 and is, relative to the transport surface of the corresponding belt 18, at an angle such that it can see the three surfaces 4, 6 and 8 of the package 2 placed on the conveyor 14

  in a second position given in the vicinity of the

output of the conveyor 13.

  The arrival of the packet 2 in the first and second positions is detected by corresponding optical detectors 30 and 31 which trigger the television camera 26 so that the latter, through the lenses 27 and 28, take two successive views of the even

  package 2 under two different angles.

  As shown in FIG. 1, each time it is triggered, the television camera 26 produces an image that is sent, in the form of

  analog signals, to an analogue-digital transducer

  32 placed at the input of a control circuit 33

  comprising two transmitters of digital reference signals

  34 and 35 triggered respectively by the detectors 30 and 31 at the same time as the camera of

television 26.

  As a result, when the packet 2 arrives in the first control position and is detected by the detector 30, the television camera 26 emits a real image of the faces 5, 7 and 9 of the packet 2, this image being transformed into signals transducer 32, while the transmitter 34 transmits

  digital signals relating to a reference image.

  The digital signals relating to both the real image and the reference image are simultaneously sent to a comparison device 36 which detects any difference between the two images and supplies the result to a processor 37. On the basis of a program given, the processor 37 determines whether the surface finish of the package 2 is acceptable or not, and if this finish is not acceptable, the processor controls, accordingly, a known type of reject device 38 placed downstream of the conveyor 12 and intended for

  reject package 2 later.

  The same process is repeated on packet 2, when it arrives in the second position of

  control in which the detector 31 triggers simul-

  at the same time the television camera 26 and the image transmitter

  to examine the faces 4, 6 and 8 of this packet 2.

  In other words, therefore, each packet 2 is subjected to two successive inspections making it possible to inspect all the faces of the packet 2 thanks to the

  conveyor system structure 3.

  According to the variant of FIG.

  conveyor system 3 uses an opto-

  electronic control 39 which simply differs from the

  device 1 by the fact that it includes opto-

  television camera electronics constituted by a television camera 40 on which the two lenses 14 and 42 corresponding to the lenses 27 and 28 of the television camera 26, are connected to the television camera 40 by corresponding optical fiber bundles

43 and 44.

R E V E N D I A T IONS

  1) Optoelectronic packet control method, characterized in that it comprises the various steps of: - successively bringing the packets (2) along a

  first conveyor device (13> defining a

  first conveying surface arranged to contact a first portion of each package (2); successively transferring the packets (2) onto a second conveyor device (14) defining a second transport surface arranged to contact a second portion of each package (2);

  - perform, through optoelectronic means

  (27, 28 or 40, 42), a first reading of a portion of the outer surface of each packet (2) as it passes along the first conveyor device (13), and a second reading of the remaining part of the

  outer surface of each package (2) when the

  it passes along the second conveyor device (14); and comparing the images obtained by these two optoelectronic means (27, 28 or 41, 42) readings with the reference images, so as to produce conformity signals allowing

  controlling a reject device (38).

  2) Method according to claim 1, characterized in that the first and second readings are performed by opto-electronic television camera means (26 or 40) designed to examine the packets

(2) from two different angles.

  ) Process according to any one of

  claims 1 and 2, caracterized in that the first

  and second surveys are carried out by sending to a

  Opto-electronic single TV camera (26 or 40) a first image and a second image of each of the packets (2) observed from two different angles. 4) Process according to any one of

  Claims 1 to 3, characterized in that the two

  images are transmitted to single TV camera opto-electronic devices (26 or 40) using

  at least one bundle of optical fibers (29 or 43, 44).